Design and Analysis of the Laser Robotic Welding System for ITER Correction Coil Case

ITER correction coil (CC) cases have characteristics of small cross section, large dimensions, and complex structure. The cases are made of heavy thick (20 mm), high strength and high toughness 316LN austenitic stainless steel. The laser welding is used for the case closure welding, due to its low heat input and deformation. According to the structural size and feature of the two types of cases, a set of laser welding workstation for the ITER CC case closure welding is designed. A slip plate module for the welding robot is designed to increase its workspace. According to the result of the movement simulation of the welding robots, the workstation is successful to cover all weld seams on the cases. Also, the welding platform and fixtures (includes the special welding tilter of the SCC) of the BTCC case and the SCC cases are designed. To verify the design structural feasibility of the welding tilter of SCC, the structural analysis for the rotating process has been formed in detail by using ANSYS. The simulating results show that the stress of the welding tilter can meet both static and fatigue criteria, and thus the basic structure is valid.